Manchester United must decide whether to send Danny Welbeck for knee surgery that could rule out the England striker for another five weeks.

United are already without midfielder Michael Carrick, who is sidelined until Christmas with an achilles injury.

On Friday, Carrick walked all 18 holes of the DP World Tour Championship second round with Rory McIlroy and Caroline Wozniacki in Dubai despite wearing a protective boot.

Injured: Danny Welbeck could be forced into knee surgery that will keep him out for another five weeks

Blow for United: Michael Carrick is sidelined until Christmas with an achilles injury

Welbeck is plagued by a cartilage problem that has led to him missing United’s last six games.

The 22-year-old is having treatment in the hope he can avoid an operation, but United fear they will have to consider keyhole surgery if his condition does not improve.

Welbeck has had two previous knee operations. Doctors decided not to remove the whole cartilage because of his young age, but it is understood that the remaining meniscus is now causing inflammation in the joint whenever he tries to run.

Marouane Fellaini could also be out for up to 10 weeks once he has surgery on a problem with ligaments in his left wrist.

Stroll: Carrick walked all 18 holes at the DP World Tour Championship in Dubai

In good company: Carrick joined Caroline Wozniacki as they watched Rory McIlroy in action

Crunch time: David Moyes will be without Carrick and possibly Welbeck for games with Spurs and Everton